Ladder scaffold



Oct. 29, 1929.

R. G. KING ET AL LADDER SCAFFOLD Filed Aug. '7, 1926 3 Sheets-Sheet l iff Il mmmw--fi 7; QF' W Oct- 29, 1929- G. KING ET An.

LADDER SCAFFOLD Fi1ed Aug. '7, 1926 :5 Sheets-Sheet, 2

0d 29, 1929- l R. G. KING ETAn.. 1,733,967

LADDER 1S CAFFOLD I Filed Aug. 7, 192e I* gks'neets-sneen s f y r 7 Z 5X '7- l 97 f A ya. #sa

.Z v v 11 Min Patented ct. 2g, 19.29`

'l f airis STATES Nr o F-FicE i RUSSELL G. KING AND HARRY c; KING, or WASHINGTON, Disrarozi. oF coLUiiiIBIvAy v LADDERl scArr'oLn Application filed August 7, 1926. Serial lim-'127355.

This'invention relates to improvements in a portable scaffold lwhich may be employed for work upon either the exterior or interior of a building, and has for one of its objects to provide a scaffold of this character which is constructed of built up ladder sections from the ground'or floor to the top of the building or at any desired height, and which is provided with scaffold platform boards securely attached tovthe ladder sections at any desired point.

Another object of this invention is the provision of an adjustable means for readily attaching the scaffold boards and the ladder sections to the Window or door frames of aVY buildingfor positioning the scaold at any desired distance from the building.

A further object of this invention is yto provide a ladder scaffold of this nature having means for securing the end portions of the platformboards to 'certain of the rungs of the ladderl sections, either singly or in end lapped relation to each other, and the furtherprovisionof means for bracing the platformboards from points remote from' manufacture, and which can be sold upon the market at a nominalcost, and'whilst we will herein illustrate, describe and claimthe preferred embodiment of our invention, we

hereby reserve the right to make such varia tions and alteration in the general structure thereof from time to time as we may deem expedient and which will neither depart ilar reference characters denote'like parts f throughout the several views of the drawings, A represents the-wall of a building from the spirit of the invention or the scope of the claims.

In thev drawings: Y v

Figure l is a front view, partly broken away, showing the applicationV of the invention to a building.

Fig. 2 is a top plan view of Figure l,

partly broken away and partly in section,

showing the means employed for attach ing the scaffold sectionsl to the window frames of a building. n

Fig. 3 is a top plan view showing-,the

specific meansjemp'loyedvfor securing the platform boards of the ladder sections to the window or door frames of a building.

Fig. i is a fragmentary detail view yof the locking means employed upon 'the Win-k dow attaching means for fthe scaffold.'l

F ig. 5 is a detail sectional view,"on the line 5 5 of Figure t showing the specific con# struction of the locking tongue of thefpawl lever employed, showing its speciiicfco-ac-J tion'with the ratchet bar of the invention.

Fig. 6 is a fragmentary perspective view of one of the swinging retaining arms car-l ried by the window attaching means for en# gaging the platform boards for securing and positioning the ladder sections relative to a wall `of a building. y n Fig; 7 is a detailview on line 7-7 of F igure 2, looking in the direction ofthe arrows, showing the means for'bi'acing the platform boards to the ladder stiles and securing the same to theframe of a door orwindow.

Fig. 8 is al fragmentary detail edge view,

partlybroken away and partly in "section, .I

showing the specific means employed "for "se: curing the platform boards to the rungs of the ladder sections and thejdiagonal brac-y4 ing frame for securing the platform boards to the stiles lof the ladderl sections. i

Figf9 isa fragmentary detail view, partly i in section, showing the specific means ein#A ployed for securing the platform bracing frame to the Stiles of the ladder sections, and'- Fig. l0 is van inverted perspective view of the plate or cleat employed for'securing the contiguous ends of the platform boards 'to the rungs of the ladder sections.

Referring to the drawings, wherein Vsimand B the window frame. Positioned 'adjacent the wall A of the building arethe`v ladder sections l. Y These ladder sectionsfl comprise a plurality of superimposedv sections extending from the ground orfloor to any desired height or to the top of a building if necessary and are positioned along a vertical line approximately between the vertical rows of Windows. Each of the ladder sections 1 is of a convenient length to permit the ready handling of the same in building up the ladder scalfold and each section is similarly formed by being slightly convergent in its longitudinal direction so that the wide end of each succeeding *superimposed section will embrace the narrow end of the section preceding it. The ladder sections comprise any desired number of rungs 2 and have each of the ends of their stiles provided with the transverse 'notches 8 and in proximity to one of the ends, for instance the upper end, with the elongated rung 4 positioned outwardly ofthe stiles and provided with the threaded ends 5 upon which are threaded the Wingnuts 6. To build up the ladder sections the notches 3 in the broad ends are positioned so as to embrace the narrow ends and engage the projecting ends of the rungs 4 and retained in suchlposition' by the wing nuts G upon their threaded ends 5, while the lower most rung v2 of the next succeeding section is seated in the notches 3 inthe adjacent ends of the next preceding section, whereby the ladder sections are built up successively to any desired height.

At any desired point along the ladder sections, but preferably opposite a window frame B, there is positioned a platform board 7 of a length adapted to rest upon two opposing rungs 2 of the ladder sections and on a plane opposite the window frame'B, but preferably adjacent the bottom portion thereof. The platform boards 7 are each formed with two rows of longitudinally alined holesS adjacent the edges thereof and preferably positioned transversely opposite each other as clearlyshown in Figure 2 and which vholes '8 may be any desired distance apart.v y n F or maintaining the platform boards and consequently the ladder sections to which they are attached, as will be hereinafter described, there is provided opposite each window frame, a scaffold board 7 and for maintain- A ing the scaffold boards 7 and the ladder sections 1 at any desired spaced relation from the wall of the building there is provided a clamping bar for each window frame B. The clamping bar consists of a supporting bar 9 having at one end the loop 10 through which is slidably mounted the ratchet bar 11 formed on its outer face with the ratchet teeth l2 and also having the loop 13 for slidably engaging the supportingbar 9. The outer ends of the supporting bar 9 and the ratchet bar 11 are provided with the screw threads 14 upon which are threaded the internally threaded sleeves 15 which are formed square in cross section as shown at 16 in Figure 3. The ends of the sleeves 15 are provided with the solid rounded heads 17. Pivotally secured to the supporting bar 9 by the bolt 18 are the bifurcated members 19 of the pawl locking lever 20 provided with the locking tooth 21, as clearly shown in Fig. 5 and adapted to ride over the teeth 12 on the ratchet face of the ratchet bar 11 when the supporting bar 9 and the ratchet bar 11 Yare moved in outward opposite directions screwing the same outwardly so that 'when the heads 17 impinge the window frame the supporting bar 9 and the ratchet bar 11 will be forced backwardly towards each other in a 'manner that the tooth 21 of the pawl lever 20 will engage a tooth 12 of the ratchet bar in such a manner that the locking lever 20 will be forcedvinwardly and held against the ratchet face of the bar 11 and be securely locked against movement until it becomes necessary to release this lever from locking engagement by a workman who must exert force by an outward pull on the locking lever 2O when it is desirable to release this clamping member, this action being due to the angular 4formation of the locking pawl asthe tooth 21 is offset from a line drawn from its pivotal point 18 to the end of the lever 20, as clearly illustrated in Figures 4 and 5.

Also pivotally mounted upon the supporting bar 9, as by the bolt. 22, are the bifurcated ends 23 ofthe scaffold board 'retaining rods 24, each havingthe screw threaded end 25 adapted to have adjustably mounted thereon the internally screw threaded head 26 of the depending pin 27, which is designed to extend at right anglesto the rod 24, whereby afterA the clamping member has been secured to the window frame the retaining rods 24 may be swung laterally to any desired degree in either direction upon the supporting bar 9of thev clamping member so that by adjusting the heads 26 on the screw threaded ends 25, the pins 27 may be positioned for bringing the pins into registration with any of the holes 8, adjacent either of the side edges of the platform boards 7 at any longitudinal point between the ladder sections to thereby maintain the platform boards 7 and the ladder sections at any desired distance from the wall of the building without the exercise of any special degree of accuracy in the longitudinal direction of the platform boards 7, so that when the board 7 is placed to rest upon a rung 2 of the ladder sections 1,the clamping member 28 is so positioned that the U-shaped portion 29 is placed beneath the rung 2.and the fiat portions eX- tending therefrom will bear against the bottom of the platform boards 7, with the holes 30 in registration with a hole 8 of the platform board 7 at either side ofthe rung 2 Y of the ladder sections, the board 7 being firinly held upon the rung 2 by the bolts 31, which pass through the respectiveholes 8 of the platform boards and the holes 30 of the clamping member and are retainedthereon by the wing nuts 32. The bolts 31, may be of sufhcient length to pass through the overlapping ends of' the platform boards 7, as clearly shown lin Figure 8, to thereby rigidly secure the platform boards 7 of the contiguous tiers of the ladder scaffold sections firmly together uponv the respectivev rungs. w l

Tofurthei' secure the platform boards 7, there is provided a bracing frame comprising the spaced side members 33 secured together by thev two cross struts 34, shown in Fig. 7 ,f

arranged in a mannerto give the bracing frame a slightly convergent formation. The upper ends of the side members 33'have secured thereon by the bolts or rivets35, thev hook members 36, adaptedv to engage the eyes 37, of the eye-bolts 38,' which are adapted to project through a pair of transversely alinedV holes 8 of the platform boards 7 and secured to the latter by the wing nuts 39. At the lower ends of the side members 33 of the bracing frame and pivotally mounted thereon by the bolts or rivets 40 are the two spaced clamping plates 41, each of the plates 41 being slightly bent at 42 and 43 to provide the inturned ends 44, the plates 41 are adapted to be swung into position at either side of the stile of the ladder sections 1 and retained in firm gripped relation thereon by the bolts 45, between their pivotal point 40 and the ladder stile l1 and retained in firm engagement with the ladder stile by the wing nuts 46.

From the foregoing described invention,

i it is clear that we have provided a ladder scaffold having many meritorious advantages, in that, the ladder sections 1 are ofa convenient length and contain any desired numberv of rungsy 2. These ladder sections are formed to readily build up the sainel in superimposed relation from the ground or floor to any desired height between the vertical rows of doors or windows'of a building, the ladder sections being built up in tiersk as the scaold progresses. After a certain number of the'ladder sections are built up to a suffi-1 cient height a platform board 7 is positioned upon certain of the rungs 2 of the ladder sections opposite a window and clamped to the respective rungs by the clamping cleats 28 and the bolts 31, as hereinafter described. The scaifold boards 7 are of any suitable length and are formed with longitudinal rows of equi-'spaced holes 8 so as to accommodate the scaffold to either narrower or wider window frames in which instance after the scaffold sections are positioned bythe narrow windows the clamping plates 28 which are secured by the bolts 31 tothe rungs 2, may be moved or adjusted to other holes 8 of the scaffold vboards so as to position the ladder sections at a lesser or greater distance apart and the eye-bolts 38 are likewise adjusted in the holes 8, so that the bracing framesmay be swung in a downwardly inclined direction so as to embrace and clamp the stiles 1 of the ladder sections at anyV convenient point below the rungs 2 to which the scadold boards have been previously secured 'and firmly clamped lto the ladderj stiles Aby the bolts 45 and their wing nuts 46. These wing nuts 46 are preferably positioned atl the inner sides of the-bracingframe so as'to be conveniently operated by a single workman.

After this has been accomplished the scaffold boards are secured to the window frames by the extension member shown in Figures 1, 2 and 7, and more specifically shown in F igures 3, 4, '5 and 6. TheeXten'sion 'members each comprise a supporting bar 9 yand a ratchet bar 12 arrangedvto have sliding engagement relative toeach other for positionling the same between the opposing facesof window or door frames of any widths and thereafter by screwing the heads 17 outwardly until the same firmly impinge the window frame, the `retroactive tendency ofthe bars 9 and 12 willv cause the tooth 2l of the locking pawl lever 2O to engage a tooth 12 of the ratchet bar l1`in ,such` a manner that the lever 20 willbe swung to lie flush against the ratchet bar 11 and firmly lock the extension members against movement.

any special regard to the true vertical aline ment thereof as the necessary adjustments can be subsequently made for rigidly maintaining the scaffold in spaced relation to the wall of a building. The specific manner of mounting the scaffold boards upon the ladder sections for maintaining the same against lateral displacement relative to each other and the specific means for maintaining the scaf foldV against inward or outward movement relative to the building in a speedy and expeditious manner are meritorious results attained by our invention.

We claim:

l. In a scaffold of the class described, the combination with parallel vertical rows of superimposed ladder sections, means for securing the ladder sections together, of scaffold boards provided with longitudinal rows of holes in proximity to the edges thereof, means to rigidly secure the scaffold boards to said ladder sections for maintaining the sec- I tions in vertical parallel spaced relation to each other, slidable extension means for readily positioning the same between the inner opposing faces of window frames, locking means carried by said extension means, and adjusting means carried by the ends of said extension means for impinging the opposing inner faces of a windowframe for causing the locking means to be firmly locked by they retractile movements of the extension means.

2. In a scaffold of the class described, the

f combination with parallel vertical rows of superimposed ladder sections, means for securing the ladder sections together, of scaffold boards provided with longitudinal rows of holes in proximity to the edges thereof, means to rigidly secure the scaffold boards to said ladder sections for maintaining the sections in vertical' parallel spaced relation to each other, slidable extension means for readily positioning the same between the inner opposing faces of window frames, locking means carried by said extension means, and rotatable adjusting means having square internally threaded sleeve shanls carried by the ends of said extension means for impinging the opposing inner faces of a -window frame for causing the locking means to be firmly locked by the retractile movements of the extension means.

3. In a scaffold of the class described, the combination with parallel vertical rows of superimposed ladder sections, means for securing the ladder sections together, of scaffold boards provided with longitudinal rows of holes in proximity to the edges thereof, means to rigidly secure the scaffold boards to said ladder sections for maintaining the sections in vertical parallel spaced relation to each other, slidable extension means for readily positioning the same between the inner opposing faces of window frames, 1ocking means carried by said extension means, j

of the holes of said platform boards to maintain said platform boards and ladder sections in vertical spaced relation to the wall of a building.

4. In a scaffold of the class described, the combination with parallel vertical rows of superimposed ladder sections, means for securing the ladder sections together, of scaffold boards provided with longitudinal rows of holes in proximity to the edges thereof, means to rigidly secure the scaffold' boards to said ladder sections for'maintaining the sections in vertical parallel spaced relation to each other, slidable extension means for readily positioning the same between the inner opposing faces of window frames, locking means carried by said extension means, rotatable adjusting means carried by the ends of said extension means for impinging the opposing inner faces of window framesfor causinof the locking means to be firmly locked by the retractile movements of the extension means, laterally swinging arms pivotally con-A nected to said extension means, andv pin carrying members adjustably mounted upon the free ends of said laterally swinging arms for engaging certain of the holes of said platform boards to maintain said platform boards and ladder sections in vertical spaced relation to the wall of a. building.

5. In a ladder scaffold of the class described, the combination with parallel vertical rows of superimposed ladder sections, means for securing the ladder sections together, of scaffold boards rigidly secured to a rung of certain of the ladder sections for maintaining the sections in vertical parallel spaced relation to each other, said scaffold boards having longitudinal rows of holes through and adjacent to the edges thereof, extension means for positioning the same between the opposing inner faces of window frames, said extension means comprising a supporting bar, a ratchet bar, means to provide for the sliding engagement of said supporting bar and said ratchet bar, a locking pawl lever pivotally mounted upon said sup-v porting bar and adapted to embrace said ratchet bar, means carried by said loc-king pawl lever to engage the ratchet teeth of said ratchet bar, and rotatable members threaded upon the outer ends of said supporting bar and said ratchet barv for firmly impinging` the opposing inner faces of Window frames, whereby when said rotatable members of said extension member are adjusted for impinging the faces of a window frame the retroactive tendency of the supporting bar relative to the ratchet bar will cause said locking pawl lever to become firmly locked upon said ratchet bar.

6. In a ladder scadold of the class described, the'combination with parallel vertical rows of superimposed ladder sections, means for securing the ladder sections together, of scaffold boards rigidly secured to 'a rung of certain ofthe ladder sections for maintaining the sections in vertical parallel spaced relation to each other, said scaffold boards having longitudinal rows of holes through and adjacent to the edges thereof, extension means for positioning the same between the opposing inner faces of Window frames, said extension means comprising a supporting bar, a ratchet bar, loops to provide for the sliding engagement of said supporting bar and said ratchet bar, a locking pawl lever pivotally mounted upon said supporting bar and adapted to embrace said ratchet bar,'a tooth carried by said locking pawl lever adapted to engage the ratchet teeth of said ratchet bar, and rotatable members threaded upon the outer ends of said supporting bar and said ratchet bar for firmly impinging the opposing inner faces of Window frames, whereby when said rotatable members of said extension members are adjusted for impinging the faces of a window frame the retroactive tendency of the supporting bar relative to the ratchet bar will cause the tooth of said locking pawl lever to become firmly locked upon said ratchet bar.

7. In a ladder scaffold of the class duescribed, the combination with parallel vertical rows of superimposed ladder sections, means for securing the ladder sections together, 'of scaffold boards rigidly secured to a rung of certain of the ladder sections for maintaining these sections in vertical parallel spaced relation to each other, said scaEold boards having longitudinal rows of holes through and adjacent the edges thereof, eX- tension means adapted to be secured between the opposing inner faces of windowframes,

said extension means comprising a supporting bar, a ratchet bar, means to provide for sliding engagement between said supporting bar and said ratchet bar, a locking pawl lever pivotally mounted upon said supporting bar and adapted to embrace said ratchet bar, means carried by said locking pawl lever to engage the ratchet teeth of said ratchet bar, rotatable members threaded uponthe outer ends of said supporting bar and said ratchet bar for firmly impingingthe opposing inner faces of window frames, whereby when said rotatable members of said extension member are adjusted for impinging the faces of a window frame the retractile tendency of the supporting bar relative to the ratchet bar will causey said ljocliing pawlflever tobecomefirmly locked' upon said ratchet bar',laterally swing-- ing arms pivotally mounted upon saidfsup'- porting bar and embracing-said ratchet bar,

said laterally swinging arms having their'y free ends screw threaded for a distance, and

means adjustably threaded upon the screw threaded ends of said arms for adjustably engaging certain of the holes of said lscafold. Y i

boards intermediate of said ladder sections, whereby to maintain said scaiold boards and said ladder sections invertical spaced relation to the wall of a building.

8. In a ladder scaffold of the class de-4 said extension means comprisingl a supporting bar, a ratchet bar, loops toprovide slid--l ing engagement between said supporting bar and said ratchet bar, a locking pawl pivotally mounted upon said supporting bar and having arms adapted to embrace said ratchet bar, means carried by said locking pawl lever adapted to engage the ratchet teeth of said ratchet bar, rotatable sleeve members threaded upon the outer ends of said supporting bar and said ratchet bar for firmly impinging the opposing inner faces of window frames, whereby when said rotatable members of said extension member are adjusted for impinging the faces of a window frame the retroactive tendency of the supporting bar relative to the ratchet bar will cause said locking pawl lever to become firmly locked upon said ratchet bar, laterally swinging arms pivotally mounted upon said supporting lbar and embracing said ratchet bar, said laterally swinging arms having their vfree ends screw threaded for a distance, and pin carrying blocks adjustably threaded upon the screw threaded ends ofsaid arms for adjustico ably engaging certain of the holes of said Y Vscaffold boards intermediate of said'k ladder sections, whereby to maintain said Ascaffold boards and said ladder sections vin vertical spaced relation to the wall of a building.

9. In a scaffold of the class described, the combination with vertical rows of superimposed ladder sections, of scaifold boards secured to said ladder sections and having longitudinal rows of holes, securing plates positioned at the underside of said boards and embracing certain of the rungs of said ladder sections, and means adapted to pass through said securing plates and certain 'of the holes of said scaffold boards for rigidly securing the scaffold boards to the ladder seci tions.

In testimony whereof` we afiix our signatures.

RUSSELL G. KING. HARRY C. KING. 

